Influence of crocin on proliferation in vitro and function of dendritic cells derived from bone marrow of children with acute leukemia / 中国实验血液学杂志

ABSTRACT

This study was purposed to investigate the effect of crocin on the proliferation in vitro and immune function of dendritic cells (DC) derived from the bone marrow of children with acute leukemia. The mononuclear cells were isolated from bone marrow of leukemia children by Ficoll-Hypaque. The experiment was divided into six groups blank control group (A), crocin 1.25 mg/ml group (B), cytokines (rhGM-CSF 75 ng/ml+rhIL-4 75 ng/ml+rhTNF-α 50 ng/ml) group (C), cytokines+crocin 0.3125, 1.25 or 5.0 mg/ml groups (D, E, F). The numbers of DC were counted and the phenotypes of DC were determined by flow cytometry on the ninth day of culture. The DC of different groups were mixed with T cells just separated from peripheral blood of another children with acute lymphoblastic leukemia, and cultured with rhIL-2 200 U/ml for 5 d. The function of DC was detected by mixed lymphocyte reaction (MLR). The results indicated that the test groups and control group all obtained a certain amount of typical DC, but the DC numbers in test groups were all higher than those in control group (P < 0.01). Cultured for 9 days, the rates of CD1a(+), CD83(+), and HLA-DR(+) in group C, D, E, F were higher than group A (P < 0.01). There was no statistically significant difference between A and B groups (P > 0.05). MLR showed that with the increasing of DC, the stimulation index of T cells in group A and B was not rising (P > 0.05); the stimulated index of T cells in group C and E was significantly rising, there was statistically significant difference between them (P < 0.01). When the number of stimulated cells was the same, the stimulation index of T cell in group E was the highest (P < 0.01). It is concluded that the capability of DC proliferation promoted by crocin alone is lower than that of its combination with rhGM-CSF, rhIL-4 and rhTNF-α, but the crocin can synergically promote the maturity of DC cooperating with rhGM-CSF, rhIL-4 and rhTNF-α. The DC induced by crocin can particularly enhance the proliferation of T cells.